1. Field
The present disclosure relates to a phosphor, a white light emitting device including the phosphor, and a method of preparing the phosphor.
2. Description of the Related Art
An electroluminescent device is an active solid state display device. In an electroluminescent device a material emits light by electroluminescence (“EL”) when an electric field is applied thereto. A dispersion type electroluminescent device includes an emissive layer which includes an electroluminescent phosphor distributed in a dielectric substance, and electrodes installed on opposite surfaces of the emissive layer. In addition, a dispersion type electroluminescent device emits light by supplying an alternating current to the electrodes.
A dispersion type electroluminescent device may be a planar light source, may be easily used in a flexible substrate, and may be formed to provide a large-size screen. A dispersion type electroluminescent device may be easily manufactured using a printing process, and may have a good resistance to temperature change. In addition, a dispersion type electroluminescent device may have lower power consumption as compared to other display devices.
A dispersion type electroluminescent device may use green and blue electroluminescent phosphors, for example, ZnS:Cu and Cl, to emit green light and blue light. However, there remains a need for a red light emitting electroluminescent phosphor. Because there remains a need for a red light emitting electroluminescent phosphor, current dispersion type electroluminescent devices use, for example, a photoluminescent phosphor to provide red light.
Accordingly, there a need remains for an electroluminescent phosphor that is capable of emitting red light.